如何在渐近线中画出球面与平面的交点

Question

我正在学习使用渐近线。我试图画出球面和平面之间的交点。下面我贴出代码。概念上似乎没有任何错误：我画了球面、前后赤道和水平面。为什么赤道不在水平面上？

代码：

import solids;
import graph3;
import three;
size(5cm);

currentprojection=orthographic(10,5,2);
currentlight=Headlamp;
real t = 1;
triple p0 =(t,t,0), p1=(-t,t,0), p2 = (-t,t,0), p3 = (t,-t,0);
nslice=4*nslice;
revolution b=sphere(O,1);
draw(surface(b),paleblue+opacity(.5));
skeleton s;
b.transverse(s,reltime(b.g,0.5),P=currentprojection);
draw(s.transverse.back,yellow);
draw(s.transverse.front,yellow);
draw(surface(p0--p1--p2--p3--cycle),brown);

Answer 1

除了你忘了提交签到之外，你做的一切都是正确的p2。

\documentclass{standalone}
\usepackage{asypictureB}
\begin{document}
\begin{asypicture}{name=AsyPlot}
import solids;
import graph3;
import three;
size(5cm);

currentprojection=orthographic(10,5,2);
currentlight=Headlamp;
real t = 1;
triple p0 =(t,t,0), p1=(-t,t,0), p2 = (-t,-t,0), p3 = (t,-t,0); //adjusted p2
nslice=4*nslice;
revolution b=sphere(O,1);
draw(surface(b),paleblue+opacity(.5));
skeleton s;
b.transverse(s,reltime(b.g,0.5),P=currentprojection);
draw(s.transverse.back,yellow);
draw(s.transverse.front,yellow);
draw(surface(p0--p1--p2--p3--cycle),brown);
\end{asypicture}
\end{document}